The present invention relates to an expanding device for supporting grinding sleeves such as emery cloth sleeves in particular.
As is known, in order to perform the surface finishing of mechanical parts in general, sleeves of emery cloth are currently used and are applied to a supporting device which is commonly termed expander and which has the function of supporting and rotating said sleeve.
Currently commercially available expanders are generally constituted by a shaft on which a rubber sleeve is provided and arranged inside the emery cloth sleeve; by axial compression, said rubber sleeve undergoes an expansion which causes the anchoring of the emery cloth sleeve.
This solution has the disadvantage that it does not perform a uniform expansion along the entire length of the support, and in particular in general there is a greater expansion in the central region with respect to the end regions. This causes said sleeve to be subjected to different wear actions, since it is unavoidably at least partially deformed by the uneven expansion of the rubber sleeve.
Furthermore, with this embodiment, difficulties are often encountered in inserting and removing the emery cloth sleeve on and from the rubber expander.
Other constructively very complicated solutions have radially expandable sectors, which do not have the possibility of ensuring perfect concentricity of the emery cloth sleeve, with subsequent difficulty in use and faster wear of said sleeve.